<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        #box{
            width: 500px;
            height: 100px;
            border: 2px solid rosybrown;
        }
    </style>
</head>
<body>
    <script type="text/javascript">
        function copy() {
            var div = document.getElementById('box');
            var newH2=document.createElement('h2')
            var text=document.getElementById('inp').value
            var newText =document.createTextNode(text)
            var input=document.getElementById('inp')
            newH2.appendChild(newText)
            div.appendChild(newH2);
        }
    </script>
    <input type="text" id="inp" >&nbsp;
    <button onclick="copy()">复制</button>
    <div id="box"> 

    </div>

</body>
</html>